From 09750ce3525129a676dec4f579aea3ad2eca1b19 Mon Sep 17 00:00:00 2001 From: Laurent Bercot Date: Mon, 9 Jan 2023 11:09:14 +0000 Subject: Add instances implementation (still needs testing) Signed-off-by: Laurent Bercot --- doc/s6-instance-create.html | 92 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 doc/s6-instance-create.html (limited to 'doc/s6-instance-create.html') diff --git a/doc/s6-instance-create.html b/doc/s6-instance-create.html new file mode 100644 index 0000000..c81dfe4 --- /dev/null +++ b/doc/s6-instance-create.html @@ -0,0 +1,92 @@ + + + + + + s6: the s6-instance-create program + + + + + + +

+s6
+Software
+skarnet.org +

+ +

The s6-instance-create program

+ +

+s6-instance-create creates a new instance of a currently supervised +instanced service. +

+ +

Interface

+ +

+     s6-instance-create [ -d | -D ] [ -P ] [ -f ] [ -t timeout ] servicedir name
+

+ +

s6-instance-create expects a running, supervised +instanced service in servicedir. +This service typically has been created by linking the result of an +s6-instance-maker invocation into +an existing scan directory.
s6-instance-create creates a new instance of that service, named +name. Depending on the given options, it may start it +immediately, or keep it down until a later +s6-instance-control invocation.
It waits for the new instance to be ready to take commands from +s6-instance-control.
It exits 0.

+ +

Exit codes

+ +

0: success
99: timeout while waiting for the instance supervisor to start
100: wrong usage
111: system call failed

+ +

Options

+ +

-d : down. The instance supervisor will be started, but the instance +itself will remain down. Any down file for the instance will be +deleted. By default, if neither the -d nor -D options have +been given, the supervisor auto-starts the instance as soon as it runs.
-D : down, and stay down. The instance supervisor will be started, +but the instance itself will remain down. A down file +will be created for the instance. By default, if neither the -d nor -D options have +been given, the supervisor auto-starts the instancece as soon as it runs.
-P : public. Everyone will be able to subscribe to the +instance supervisor's notification. By default, only processes running with the same gid +as the instanced service can subscribe to it.
-f : force permissions. You should never need to use this +option, it is only there for testing purposes.
-t timeout : if the instance supervisor has not started +after timeout milliseconds, s6-instance-create will print a message +to stderr and exit 99. By default, timeout is 0, which means no time +limit.

+ +

Notes

+ +

s6-instance-create is similar to +s6-svlink, because it uses the same underlying +library functions. Under the hood, an instance is a regular service running +on a supervision tree that is specific to the instanced service, and +s6-instance-create adds a service directory to that tree and ensures it gets +supervised.
If the template for the service is logged, then s6-instance-create will +wait until supervisors have been spawned for both the instance and its logger.

+ + + -- cgit v1.2.3